JP2001045772A - 3-level inverter or pwn cycloconverter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce price and size by arranging a semiconductor switch and the chip unit of a diode for composing the main circuit of a three-level inverter in parallel on the same structure as the configuration of one arm and connecting them. SOLUTION: When a semiconductor switch chip used for a three-level inverter and a diode chip are arranged on a same substrate 9 and are connected, the semiconductor chip and the chip of diodes that are parts excluding a capacitor out of the main circuit of a three-phase three-level inverter are composed by a compound module. Then, each chip and a connection part are arranged on the same substrate, an alumina plate, or the like, insulation treatment is made when insulation is required, and each component is connected by a copper foil pattern 7, a wire 8, or the like as one module 9 as shown in a circuit diagram for applying to the three-level inverter, thus achieving the three-level inverter in a complex configuration without increasing costs and size.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inverter and the like using a module in which semiconductor switches and diodes constituting a three-level inverter for converting a DC voltage input into a desired AC voltage output are arranged and connected on the same structure. About.

[0002]

2. Description of the Related Art FIG. 2 shows a basic configuration of a power converter of a three-level inverter. At present, there is a single insulated gate bipolar transistor (hereinafter referred to as "IGBT") module in which a diode is connected in antiparallel with a semiconductor switch, and a 2in1 in which an IGBT and an antiparallel diode are connected in series. (Two-in-one) IGBT
Since a 6-in-1 (six-in-one) IGBT module in which three phases of the module are combined into one module is mainstream, there was no problem in realizing a two-level pulse inverter, but the configuration of the main circuit differs from that of the two-level inverter. In order to realize a three-level inverter, since the three-level inverter has not been applied to a low-voltage general-purpose inverter so far, the external shape and cost have increased. The same can be said for a PWM cycloconverter using a semiconductor switch or the like.

[0003]

SUMMARY OF THE INVENTION The present invention is to solve the above-mentioned problems, and to provide a low-cost and small-sized composite module for a three-level inverter or a PWM cycloconverter using a plurality of semiconductor chips. It is in.

[0004]

According to a first aspect of the present invention, a DC voltage between a P (positive) side and an N (negative) side is divided into two and an output voltage is divided into three levels. (Hereinafter referred to as a “three-level inverter”), in which a semiconductor switch chip having a diode chip connected in anti-parallel is connected with a top collector connected to the P side and an emitter connected to the P side. Connected to the th collector,
Connect four in series so that the second emitter is connected to the third collector, the third emitter is connected to the fourth collector, and the fourth emitter is connected to the N side. An output terminal is taken out from the connection point between the second collector and the third emitter, the cathode of the diode chip is connected to the connection point between the first emitter and the second collector from the P side, and the anode of the diode chip is connected to a DC voltage. Is connected to the neutral point that is divided into two, and 3
The anode of the diode chip is connected to the connection point of the fourth emitter and the fourth collector, and the cathode of the diode chip has a unit connected to a neutral point obtained by dividing the DC voltage into two, and has a one-arm configuration. 3 circuits
All the uppermost collectors are connected to the P side, all the fourth emitters are connected to the N side, and the second emitter and the third collector are connected to each other. The anode of the diode chip and the cathode of the diode chip connected to the third emitter and the fourth collector are arranged and connected in parallel on the same structure at a neutral point. According to a second aspect of the present invention, there is provided a rectifying unit for rectifying an AC voltage to convert it into a DC voltage, and the three-level inverter, wherein a rectifying diode used for the rectifying unit has the same structure as the inverter module of the first aspect. It is characterized by being arranged and connected on an object. Further, the invention according to claim 3 further comprises a rectifier for rectifying an AC voltage and converting it to a DC voltage, a braking circuit for driving the three-level inverter and a discharge resistor for braking, and a rectifier diode used for the rectifier. And a semiconductor switch and a diode used in the braking circuit are arranged and connected on the same structure as the inverter module of the first aspect. The invention according to claim 4 uses a module mounted and wired on the same structure as the inverter module of claim 1 in a three-level inverter using semiconductor switches and diodes of surface-mount discrete components. It is characterized by: Further, the invention of a multi-level inverter according to claim 5 is characterized in that the three-level inverter according to claim 4 is connected in multiple stages. According to a sixth aspect of the present invention, in a multilevel inverter using a semiconductor switch and a diode of a surface mount discrete component, a module in which the semiconductor switch and the diode are mounted and wired on the same structure is used. And With the above configuration, it is possible to use a module in which a plurality of semiconductor switches and diodes necessary for realizing a circuit of a three-level inverter are arranged and connected on the same structure such as a board or an aluminum plate in a chip or a mold state for each chip. The size and cost of the three-level inverter can be reduced. Furthermore, the invention of a PWM cycloconverter according to claim 7 is a PWM cycloconverter for directly converting a commercial AC voltage directly to an AC voltage of an arbitrary frequency, wherein a plurality of semiconductor switch chips and diode chips constituting the PWM cycloconverter are provided. Are arranged and connected on the same structure. The invention according to claim 8 is characterized in that, in a PWM cycloconverter using a semiconductor switch and a diode of a surface mount discrete component, a module in which the semiconductor switch and the diode are mounted on the same structure and wired is used. And The invention according to claim 9 is characterized in that the PWM cycloconverter according to claim 7 or 8 is multiplexed. With the above configuration, it is possible to use a module in which a plurality of semiconductor switches and diodes necessary for realizing a circuit of the PWM cycloconverter are arranged and connected on the same structure such as a board or an aluminum plate in a chip or a mold state for each chip. The size and cost of the PWM cycloconverter can be reduced. The invention according to claim 10 is characterized in that the connection relationship according to claim 1 applied to an NPN semiconductor switch is similarly applied to a PNP semiconductor switch. With the configuration described above, it is possible to realize the miniaturization and cost reduction of the three-level inverter circuit using the PNP type semiconductor switch.

[0005]

2 is a circuit diagram showing a three-phase three-level inverter. FIG. 2 (a) shows a main circuit of the three-phase three-level inverter, and FIG. 2 (b) shows a three-phase three-level inverter. FIG. 2C shows an example of a rectifying unit on the input side of FIG.
It is a circuit diagram showing an example of a braking circuit part of a level inverter. In FIG. 2A, a terminal P is a positive terminal, and a terminal N is a negative terminal. As shown in FIG.
The output of the rectifier of (b) is connected, and a rectified voltage obtained by rectifying the AC voltage is applied between the terminal P and the terminal N. A series connection circuit of capacitors 1C1 and 1C2 is connected between the terminals P and N, and the rectified voltage is applied to the capacitors 1C1 and 1C1.
U-phase, V-phase, and W-phase of three-phase three-level inverters which are smoothed by a series connection circuit of C2 and connected in parallel, respectively.
Applied to the main circuit of the phase. The U-phase main circuit 1 includes, for example, I
GBTs 1S1, 1S2, 1S3, 1S4 and respective IGBTs are provided with freewheel diodes 1D2, 1D.
First, second, third, and fourth semiconductor switch chips in which 3, 1D5, and 1D6 are connected in anti-parallel, and the cathode of the first clamp diode 1D1 is connected to the first semiconductor switch chip and the second semiconductor switch chip. Connect to the connection point,
The anode of the second clamp diode 1D4 is connected to the third
A first clamp diode connected to a connection point between the semiconductor switch chip and the fourth semiconductor switch chip;
And the cathode of the second clamp diode 1D4 are both connected to the connection point of the capacitors 1C1 and 1C2. Similarly, the V-phase main circuit 2
The BTs 2S1, 2S2, 2S3 and 2S4 and the respective IGBTs are provided with freewheeling diodes 2D2 and 2D.
First, second, third, and fourth semiconductor switch chips in which 3, 2D5, and 2D6 are connected in anti-parallel, and the cathode of the first clamp diode 2D1 is connected to the first semiconductor switch chip and the second semiconductor switch chip. Connect to the connection point,
The anode of the second clamp diode 2D4 is connected to the third
A first clamp diode connected to a connection point between the semiconductor switch chip and the fourth semiconductor switch chip;
And the cathode of the second clamp diode 2D4 are both connected to the connection point of the capacitors 1C1 and 1C2. Similarly, the W-phase main circuit 3
The BTs 3S1, 3S2, 3S3, 3S4 and the respective IGBTs are provided with freewheeling diodes 3D2, 3D.
First, second, third, and fourth semiconductor switch chips in which 3, 3D5, and 3D6 are connected in anti-parallel, and the cathode of the first clamp diode 3D1 is connected to the first semiconductor switch chip and the second semiconductor switch chip. Connect to the connection point,
The anode of the second clamp diode 3D4 is connected to the third
The first clamp diode 3D1 is connected to a connection point between a semiconductor switch chip and a fourth semiconductor switch chip.
And the cathode of the second clamp diode 3D4 are both connected to the connection point of the capacitors 1C1 and 1C2.

FIG. 1 shows an example in which a semiconductor switch chip and a diode chip used for a three-level inverter are arranged and connected on the same substrate 9, and the three-level inverter shown in FIG.
Capacitor 1C in the main circuit of the phase 3 level inverter
It is composed of a module in which semiconductor switch and diode chips other than 1, 1C2 are combined. In FIG. 1, 1S1 to 1S4, 2S1 to 2S4, 3S1
To 3S4 are semiconductor switches, 1D1 to 1D6, 2D1 to
2D6, 3D1-3D6 are diode chips, 4,
Reference numerals 5 and 6 denote input connection portions of P, N and C in FIG.
U, V, and W are output connection portions of U, V, and W in FIG.
1, 1B2, 2B1, 2B2, 3B1, 3B2 are semiconductor switch control signal connection parts, and 1T1, 1T2, 2T1,.
2T2, 3T1, and 3T2 indicate connection portions. Each chip and connecting part are placed on the same substrate or aluminum plate. If insulation is required, perform insulation treatment and connect each part with copper foil pattern 7, wire 8, etc. as shown in the circuit diagram Thus, one module 9 is applied to a three-level inverter. In the above embodiment, the NPN
Although the present invention has been described with reference to an example of a semiconductor switch of the type, the present invention is not limited to this, and the present invention can be similarly applied to a circuit of a three-level inverter using a PNP semiconductor switch.

Also, it is advantageous to combine the diodes D1 and D2 in FIG. 2B used in the rectifier with the module of the inverter so as to make it more compact. FIG. 2C shows capacitors 1C1 and 1C2.
1 shows a braking circuit unit that consumes electric energy and the like into heat energy by a braking resistor R1, and an IGBT or the like is used for a semiconductor switch S1 for flowing a current through the braking resistor R1.
It is advantageous to combine the semiconductor switch S1, the diode, and the like with the module of the inverter section, since the configuration can be made more compact.

FIG. 3 shows a circuit example of a PWM cycloconverter. FIG. 3A shows one bidirectional switch BS as a unit of the circuit configuration. FIG. 3B shows a PWM cycloconverter module 10 using three bidirectional switches BS. FIG. 3C shows a module 2 in which the PWM cycloconverters are arranged in parallel.
0, and FIG.
Shown are modules 30 in parallel.

FIG. 4 shows a IGBT or GTO (gate turn-off thyristor) which is a one-way semiconductor switch to realize one bidirectional switch BS shown in FIG.
2 are connected in series or in parallel, and a specific circuit using a diode or the like is shown. FIG. 4A shows that two collectors S1 and S2 of the IGBT are connected to each other (connection point T2), the anodes of the diodes D1 and D2 are connected to the connection point T2, and the cathode of the diode D1 and the emitter of the IGBTS1 are connected. (Connection point T1), and connects the cathode of the diode D2 and the emitter of the IGBTS2 (connection point T3).
The operation of the circuit of FIG. 4A is as follows. When S1 of the IGBT is turned on, a current flows through T1 → S1 → diode D2 → T2, and when S2 of the IGBT is turned on, a current flows through T2 → S2 → diode D1 → T1. Switch BS
Is formed. In FIG. 4B, two IGBTS1 and S2 are connected to each other at the emitter (connection point T2), and two diodes D1 and D2 are connected to each other at the cathodes and connected to the connection point T2. The bidirectional switch BS is formed by connecting the anode of the diode D1 to the emitter of the IGBTS1 (connection point T1) and connecting the anode of the diode D2 to the emitter of the IGBTS2 (connection point T3).
The operation of the circuit of FIG. 4B is as follows. When S1 of the IGBT is turned on, a current flows through T3 → diode D2 → S1 → T1, and when S2 of the IGBT is turned on, a current flows through T1 → diode D1 → S2 → T3. Switch BS
Is formed. FIG. 4C shows a series connection circuit connecting the collector of IGBTS1 and the anode of diode D1 and a series connection circuit connecting the collector of IGBTS2 and the anode of diode D2, respectively.
And the emitter of the IGBTS1 (connection point T1), and the cathode of the diode D1 and the IGBTS2
The bidirectional switch BS is connected in parallel (connection point T3) and connected in parallel. The operation of the circuit of FIG.
When S1 of the IGBT is turned on, a current flows through T1 → S1 → diode D1 → T3, and when S2 of the IGBT is turned on, current flows through T3 → S2 → diode D2 → T1 to form a bidirectional switch BS. FIG. 4 (d)
A series connection circuit connecting the emitter of IGBTS1 and the cathode of diode D1, and a series connection circuit connecting the emitter of IGBTS2 and the cathode of diode D2,
The anode of the diode D2 is connected to the collector of the IGBTS1 (connection point T1), and the anode of the diode D1 is connected to the anode of the IGBTS2 (connection point T).
3) Bidirectional switches BS connected in parallel. FIG.
The operation of the circuit of (d) is as follows. When S1 of the IGBT is turned on, a current flows through T3 → diode D1 → S1 → T1,
When S2 of the IGBT is turned on, T1 → diode D
A current flows from 2 to S2 to T2, and a bidirectional switch BS is formed.

FIG. 4E shows a bidirectional switch BS in which GTOs (gate turn-off thyristors) S1 and S2 are connected in anti-parallel. FIGS. 4A to 4D show IGBTs.
When a signal is applied to the base, the IGBT turns on. When there is no signal, the IGBT turns off. On the other hand, the GTO turns on when a positive pulse is applied to the gate.
Thereafter, even if there is no signal at the gate, the gate is kept on, and the gate is turned off when a negative pulse is applied to the gate or when the gate voltage becomes lower than the holding current. Therefore, the operation of the circuit of FIG. 4E is such that when a positive pulse is applied to the gate of S1 of GTO, GT
O S1 turns on. T when S1 turns on
A current flows from 1 to S1 to T3. Then, when a negative pulse is applied to the gate or becomes equal to or lower than the holding current, S1 is turned off.
Conversely, when a positive pulse is applied to the gate of S2 of the GTO, S2
2 is turned on, and the current flows from T3 to S2 to T1, and continues to flow until a negative pulse is applied to the gate or the holding current becomes lower. Thus, the bidirectional switch BS of FIG. 4E is formed.

FIG. 5 shows the pattern of the PWM cyclo-converter of FIG. 3B using three bidirectional switches BS, and shows the IGBTs S1 and S2 and the diode D of FIG.
FIG. 6 is a perspective view of a module 10 of a bidirectional switch circuit configured using D1, D2, and FIG.
FIG. 2 is a structural diagram of a PWM cycloconverter module according to the present invention including: In FIG. 5, 1S11 of the IGBT
And 1S12 correspond to S1 and S2 of the IGBT of FIG. 4A, and diodes 1D11 and 1D12 of FIG.
Of the diodes D1 and D2. Also, the connection point terminals 1T1, 1R1, and 1P1 in FIG.
It corresponds to the connection points T1, T2, T3 in (a). G in FIG.
11 and G12 are gate lines for controlling 1S11 and 1S12. Exactly the same applies to the IGBTs 1S21 and 1S22 of the second group, the diodes 1D21 and 1D22 of the second group, and the connection point terminals 1T2 and 1R2 of the second group, which can be seen in the middle part of FIG.
That is, 1S21 and 1S22 of the IGBT are shown in FIG.
IGBTs S1 and S2, and a diode 1D21
4D correspond to the diodes D1 and D2 in FIG. 4A, and the connection terminals 1T2 and 1R2
This corresponds to the connection points T1 and T2 in FIG. G21 and G22 in FIG. 5 are gate lines for controlling 1S21 and 1S22. Similarly, the third group of IGs shown in the lower part of FIG.
The same applies to the BTs 1S31 and 1S32, the third group of diodes 1D31 and 1D32, and the third group of connection terminals 1T3 and 1R3. That is, 1S31 and 1S32 of the IGBT are the IGBTs of FIG.
The diodes 1D31 and 1D correspond to S1 and S2 of the BT.
32 corresponds to the diodes D1 and D2 in FIG. 4A, and the connection terminals 1T3 and 1R3 correspond to the connection points T1 and T2 in FIG. 4A, respectively. G31 and G32 in FIG. 5 are gate lines for controlling 1S31 and 1S32. In FIG. 6, which is a structural diagram of the PWM cycloconverter module including the bidirectional switch circuit module of FIG. 5, 10 is a bidirectional switch circuit module, and 61 is 3φ.
An input terminal, 62 is an output terminal, 63 is an insulating plate, 64 is a case, 65 is a base plate, 66 is a mounting hole, and 67 is a gate terminal. As described above, the PWM whose main circuit configuration is complicated
Even a cycloconverter can be realized without increasing cost and size by applying a module in which semiconductor switch / diode chips are arranged and wired on the same structure such as a substrate.

FIG. 7 shows a pattern of the PWM cyclo-converter of FIG. 3C using six bidirectional switches BS, which shows S1 and S2 and a diode D of the IGBT of FIG.
FIG. 8 is a perspective view of a module 20 of a bidirectional switch circuit configured using D1, D2, and FIG.
FIG. 2 is a structural diagram of a PWM cycloconverter module according to the present invention including: 7, a module 20 is obtained by connecting the modules 10 of FIG. 5 in two rows in parallel.
Therefore, IGBTs 1S11 and 1S12 belonging to the first module in the left column are S1 and S1 of the IGBT in FIG.
7, the diodes 1D11 and 1D12 in FIG. 7 correspond to the diodes D1 and D2 in FIG. 4A, and the connection terminals 1T1, 1R1, and 1P1 in FIG.
The same applies to the connection points T1, T2, and T3 in (a). Hereinafter, the second group in the middle part of FIG.
The same is true for groups. Exactly the same is true for the second module on the right side of the figure. That is, 2S11 and 2S12 of the IGBT are the IGBTs of FIG.
It corresponds to S1 and S2 of BT, and the diode 2D11 of FIG.
And 2D12 correspond to the diodes D1 and D2 in FIG. 4A, and the connection point terminals 2R1 and 2P1 in FIG. 7 correspond to the connection points T2 and T3 in FIG. 4A, respectively. The same applies to the second group in the middle part of FIG. 7 and the third group in the lower part. In FIG. 8, which is a structural diagram of the PWM cycloconverter module including the bidirectional switch circuit module of FIG. 7, 20 is a bidirectional switch circuit module, 81 is a 3φ input terminal, 82 is an output terminal, 83 is an insulating plate, 84 Is a case, 85 is a base plate, 86 is a mounting hole, and 87 is a gate terminal. As described above, even in the case of a two-parallel PWM cycloconverter having a complicated main circuit configuration, the cost is reduced by applying a module in which semiconductor switch / diode chips are arranged and wired on the same structure such as a substrate. It can be realized without increasing the size.

FIG. 9 shows the pattern of the PWM cyclo-converter of FIG. 3D using nine bidirectional switches BS, as shown by S1 and S2 and the diode D of the IGBT of FIG.
10 is a perspective view of a module 30 of a bidirectional switch circuit configured using D2, and FIG.
FIG. 3 is a structural diagram of a PWM cycloconverter module according to the present invention including a zero. In FIG. 9, a module 30 is obtained by connecting the modules 10 of FIG. 5 in three rows in parallel. Therefore, 1S11, 1S12 and below of the upper first group IGBT belonging to the first module 10 in the left column,
The same applies to 1S21, 1S22 and below in the second group in the middle row, and 1S31 and 1S32 and below in the third group in the lower row, and the upper first section belonging to the second module 10 in the middle row.
The same applies to 2S11 and 2S12 and below in the group IGBT, 2S21 and 2S22 and below in the second group in the middle, and 2S31 and 2S32 and below in the third group in the lower.
The same applies to 3S11 and 3S12 and below of the upper first group IGBT belonging to the third module 10 in the right column, 3S21 and 3S22 and below of the middle second group, and 3S31 and 3S32 and below of the lower third group. The same is true for In FIG. 10, which is a structural diagram of a PWM cycloconverter module including the bidirectional switch circuit module of FIG. 9, 30 is a bidirectional switch circuit module, 91 is a 3φ input terminal, 92 is an output terminal, 93 is an insulating plate, 94 Is a case, 95 is a base plate, 96 is a mounting hole, and 97 is a gate terminal. As described above, even in the case of a three-parallel PWM cycloconverter having a complicated main circuit configuration, the cost is reduced by applying a module in which semiconductor switch / diode chips are arranged and wired on the same structure such as a substrate. It can be realized without increasing the size.

In addition to the above, semiconductor switches and diodes, which are surface-mount discrete components, are also described.
It is advantageous to use a module mounted and wired on the same structure as the inverter module described above. The same applies to the PWM cycloconverter, and it is advantageous to use a module in which semiconductor switches and diodes, which are discrete components mounted on a surface, are mounted and wired on the same structure as the above-described PWM cycloconverter module. In addition, if a module in which a semiconductor switch and a diode of a surface mount discrete component are mounted on the same structure and wired is used, 3
Multi-level inverters above the level can be realized without increasing cost and size. If such three-level inverters are connected in multiple stages, a multi-level inverter can be realized without increasing cost and size. By multiplexing the above-described PWM cycloconverters, a multiplexed PWM cycloconverter can be realized without increasing cost and size.

[0015]

As described above, in a commercially available IGBT module, a three-level inverter or a PWM sachro converter having a complicated configuration which is difficult to realize is arranged by wiring semiconductor switch / diode chips on the same structure such as a substrate. By applying such a module, it can be realized without increasing cost and size. At the same time, since the connection between the elements can be shortened, there is also an effect of suppressing a surge voltage and unnecessary noise caused by wiring inductance during switching.

[Brief description of the drawings]

FIG. 1 shows an example of a module configuration for a three-level inverter according to a first embodiment of the present invention.

FIG. 2 is a diagram showing a main circuit of a three-level inverter unit.

FIG. 3 is a diagram showing various main circuits of the PWM cycloconverter.

FIG. 4 is a diagram showing a specific example in which the bidirectional switch BS of FIG. 3 is realized by using two unidirectional semiconductor switches in series or in parallel, and further using a diode or the like.

FIG. 5 shows a PW of FIG. 3B according to the second embodiment of the present invention.
FIG. 5 is a perspective view of a circuit device realized by using the IGBT and the diode of FIG.

FIG. 6 is a structural diagram of the present embodiment in which a module is formed including the module circuit 10 of FIG.

FIG. 7 shows a modification of the second embodiment of the present invention,
FIG. 5C is a perspective view of a circuit device realized by using the IGBT and the diode of FIG. 4A for the pattern of the PWM cycloconverter of FIG.

8 is a structural diagram of the present embodiment in which a module including the module circuit 20 of FIG. 7 is formed.

FIG. 9 shows a modification of the second embodiment of the present invention,
FIG. 5D is a perspective view of a circuit device realized by using the IGBT and the diode of FIG. 4A for the pattern of the PWM cycloconverter of FIG.

FIG. 10 is a structural diagram of the present embodiment in which a module is formed including the module circuit 30 of FIG. 9;

Continuation of the front page (72) Inventor Sadao Ishii 2-1 Kurosaki Castle Stone, Yawatanishi-ku, Kitakyushu-shi, Fukuoka F-term (reference) 5H007 CA01 CA05 CB05 CC23 HA03 HA04

Claims (10)

[Claims] An inverter unit (hereinafter referred to as a "three-level inverter") that divides a DC voltage between a P (positive) side and an N (negative) side into two and outputs an output voltage at three levels. ,
A semiconductor switch chip having a diode chip connected in anti-parallel is connected with a top collector connected to the P side, an emitter connected to the second collector, a second emitter connected to the third collector, The fourth emitter is 4
Connected in series such that the fourth emitter is connected to the N-side and the fourth emitter is connected to the N-side, and the output terminal is taken out from the connection point of the second collector and the third emitter from the P-side. The cathode of the diode chip is connected to the connection point between the first emitter and the second collector from the side, the anode of the diode chip is connected to the neutral point obtained by dividing the DC voltage into two, and the third emitter from the P side. And 4
The anode of the diode chip is connected to the connection point of the third collector, and the cathode of the diode chip has a unit connected to a neutral point obtained by dividing the DC voltage into two, and has one arm. All the uppermost collectors viewed from the P side of each arm are connected to the P side, all the fourth emitters are connected to the N side, and the second emitter and the third collector are connected. A three-level inverter, wherein an anode of a diode chip and a cathode of a diode chip connected to a third emitter and a fourth collector are arranged and connected in parallel on the same structure at a neutral point. 2. The rectifier according to claim 1, further comprising a rectifier for rectifying an AC voltage and converting the rectified voltage into a DC voltage, and the three-level inverter, wherein a rectifier diode used for the rectifier is disposed on the same structure as the inverter module of claim 1. A three-level inverter characterized by being connected. 3. A rectifying unit for rectifying an AC voltage and converting it to a DC voltage, a braking circuit unit for driving the three-level inverter and a discharging resistor for braking, and a rectifying diode used for the rectifying unit and used for a braking circuit. A three-level inverter, wherein the semiconductor switch and the diode are arranged and connected on the same structure as the inverter module of claim 1. 4. A three-level inverter using semiconductor switches and diodes of surface mount discrete components, wherein the three-level inverter uses a module mounted and wired on the same structure as the inverter module of claim 1. 5. A multi-level inverter in which the three-level inverter according to claim 4 is connected in multiple stages. 6. A multi-level inverter using a semiconductor switch and a diode of a surface mount discrete component, wherein the semiconductor switch and the diode are mounted on the same structure and wired. 7. A PWM cycloconverter for directly converting a commercial AC voltage to an AC voltage having an arbitrary frequency, wherein a plurality of semiconductor switch chips and diode chips constituting the PWM cycloconverter are arranged and connected on the same structure. PWM cycloconverter characterized by the following. 8. A PWM cycloconverter using a semiconductor switch and a diode of a surface mount discrete component, wherein the semiconductor switch and the diode are mounted on the same structure and wired using a module.
Cyclo converter. 9. A PWM cycloconverter in which the PWM cycloconverters according to claim 7 are multiplexed. 10. A three-level inverter, wherein the connection relationship according to claim 1 applied to an NPN type semiconductor switch is similarly applied to a PNP type semiconductor switch.